A decision problem as used to define the classes NP and P is of the form: does there exist an x such that F(x) = 1, where F is a P-time computable function.
If you can solve that problem in P-time then you can also solve the functional version (find an x for which F(x) = 1) in P-time simply by setting each bit to a value for which the decision problem is satisfiable, one by one.
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A decision problem as used to define the classes NP and P is of the form: does there exist an x such that F(x) = 1, where F is a P-time computable function.
If you can solve that problem in P-time then you can also solve the functional version (find an x for which F(x) = 1) in P-time simply by setting each bit to a value for which the decision problem is satisfiable, one by one.